Rotary engine.



PATENI'ED SEPT. 17, 1907.

H. J. DUNCAN. ROTARY ENGINE.

APPLICATION nun JAN. 31, 1907.

2 SHEEN-SHEET l.

I A. T F

PATENTBD SEPT. 17, 1907,

H. J. DUNCAN.

ROTARY ENGINE.

APPLICATION rum) JAN. 31, 1907.

2 SHEETS-SHEET 2.

'VVLWA WOL UNITED STATES PATENT OFFICE.

HENRY .T. DUNCAN, OF ALPENA, MICHIGAN.

ROTARY ENGINE To all whom it may concern:

Be it known that I, HENRY J. DUNCAN, a citizen of the United States, residing at Alpena, in the county of Alpena and State of Michigan, have invented new and useful Improvements in Rotary Engines, of which the following is a specification.

My invention relates to rotary engines; and it seeks to provide a simple, compact and inexpensive rotary engine, constructed with a view of utilizing the expansion of steam to the best advantage, and one susceptible of being readily reversed when occasion demands.

The invention will be fully understood from the following description and claims when the same are read in connection with the accompanying drawings, forming part of this specification, in which:

Figure l is a longitudinal vertical section of the rotary engine constituting the preferred embodiment of my invention, with parts of the reversing gear shown by dotted lines and other parts thereof shown by full lines. Fig. 2 is a side elevation of the rotary engine, with the shaft in section and showing the parts of the gear for operating the cut-off valves in the positions which said parts occupy when the cut-off valves are in position to admit steam to the interior of the casing or piston cylinder. Fig. 3 is asection taken in the plane indicated by the. line 33 of Fig. 1, looking downward. Fig. 4 is a detailside elevation, partly in sec tion, illustrative of the piston and the elements carried thereby.

Similar letters of reference designate corresponding parts in all of the views of the drawings.

The casing of my novel engine may be of any construction compatible with my invention without involving departure from the scope thereof. I prefer, however, to have the said casing comprise a bed A, a hollow intermediate section B fixed to and rising from the bed A, and side plates 0 arranged at opposite sides of the intermediate portion B and connected thereto by bolts 11 or other suitable means. Interiorly the intermediate section B of the casing is shaped as best shown in Fig. .l-that is to say, it is provided with oppo site portions 1), which describe parts of a common circle, and also witlropposite abutments B which are arranged intermediate the portions 1) and have their faces (I arranged to describe portions of a common circle of less diameter than that of the circle in which the portions 1; are arranged. The said section B is also provided, as best shown in Fig. 1, with opposite steam chests D, each oi which has diametrically opposite exhaust ports 0 c and a steam-inlet port (1; the latter being arranged midway between ports 0 and c as shown. Above the said intermediate section B of the casing, is arranged a steam supply pipe E, which may be and preferably is equipped with a centrifugal or other suitable governor (not shown), and from the said Specification of Letters Patent.

Application filed January 31, 1907. Serial No. 355,141.

Patented Sept. 17, 1907.

pipe E extend pipes F which have for their office to conduct live steam to the ports d in chests D. Intermediate the interior of the casing section B and each of the chests D are ports 6 e, the purpose of which will be presently pointed out. Loosely mounted on stub shafts f carried by and extending inward from the side plates of the casing O are four wheels G. These wheels G are arranged parallel and adjacent to the side plates 0, and are designed to effect the inward movement of the blades on the piston hereinafter described.

Journaled in suitable bearings in the side plates 0 of the casing and extending transversely through the casing is a shaft H, and on the said shaft is fixed the piston I. This piston I comprises a hub g, a web i, and a wide peripheral portion h which is connected by the web to the hub and is provided with diametrically opposite projections h! and recesses k at opposite sides of the same, and is also provided with peripheral side flanges k on which are packing rings h designed to bear against the casing section B with a view of rendering the piston steam tight. The said piston is provided in each of the ends of the hub 9, Figs. 3 and 4 with diametrically-opposite notches j, and it is also provided in its peripheral portion h and web 11 with diametrically opposite sockets it. These sockets k receive radially-movable blades J which are disposed between the flanges k and have their inner .portions bifurcated as best shown in Fig. 3 to form arms Z which rest at opposite sides of the web '5 and have their inner ends disposed in the hub notches j. Extending outward from the said arms 1 are stub shafts m, and on these stub shafts m are loosely mounted wheels K which are designed to engage the before described wheels G so as to force the blades J inward or toward the center of the piston at the proper times so as to enable the said blades to pass the abutments B. During the completion of the said inward movements of the blades .T, the ends of the blade arms Z are received in the hub notches j, and hence it will be apparent that there is no liability of the blades being bent when the wheels K pass under the wheels G. At this point it is well to state that the blades J are normally pressed outward by suitable springs L, and that said blades are moved inward against the action. of said springs by the wheels G, cooperating with the wheels K on the blades.

M M are reversing cylinders arranged and adapted to be turned about their axes in the chests D. N N are lever arms fixed to said cylinders M, and P is a link connecting the said arms, whereby it will be apparent that the cylinders may be synchronously rolled or turned, for a purpose presently set forth. Each of the cylinders M is provided with a comparatively large port m arranged to register with the steam inlet port d of the chest D, a port n designed in one position of the cylinder to register with the before described port a, a port 19 designed in the other position of the cylinder to register with before described port 6, a passage '1 designed in one position of the cylinder to effect communication between the port a and the exhaust port 0, and a passage 3 designed in the other position of the.

cylinder to effect communication between the port a and the exhaust port 0.

U U are hollow cut-off valves arranged and adapted to be rocked in the cylinders M. Each of these valves U is provided with a port t designed to be moved into and out of registration with the adjacent cylinder port It, and a port a designed to be moved into and out of registration with the adjacent cylinder port 19.

The valves U are operated from the shaft H through the medium of the gear illustrated which comprises arms P fixed to the valves, a rod Q connecting said arms, an eccentric R iixed on shaft H, and an eccentric strap S receiving the eccentric R and having an arm T connected to one of the arms P.

It will be gathered from the foregoing that in the practical operation of my novel engine, a jet of steam from one valve acts against one blade of the piston at the same time that a jet of steam from the other valve is acting against the other blade, and hence there is no pressure imposed on the shaft H. It will also be gathered that incident to each revolution of the piston two jets of steam emanate from each valve, and one jet exerts pressure against one blade of the piston and the other jet exerts pressure against the other blade of the piston, and further that immediately subsequent to the entry of each jet of steam into the space between the piston and the casing, such space is cut off from the valve so as to secure expansion of the steam to the best advantage.

When it is desired to reverse the engine, all that the operator has to do is to throw the arm N at the right in the direction indicated by the arrow in Fig. 1, so as to cause the passage 7' of the cylinder M at the right to effect communication between the ports a and 0 the port p of said cylinder M at the right to register with the port 0, the passage s of the cylinder M at the left to effect communication between the port 6 and the exhaust port 0, and the port n of the cylinder M at the left to register with the port a.

I have. entered into a detailed description of the construction and relative arrangement of the parts embraced in the present and preferred embodiment of my invention in order to impart a full, clear and exact understanding of the said embodiment. I do not desire, however, to be understood as confining myself to the said specific construction and arrangement of parts as it is obvious that in practice various changes in the form, construction and relative arrangement of parts may be made without involving departure from the scope of my invention as defined in the claims appended.

Having described my invention, what I claim and desire to secure by Letters-Patent, is:

1. In a rotary engine, the combination with a casing containing an abutment, and a wheel mounted in the easing; of a rotary piston, a blade carried by and movable with respect to the piston, and a wheel carried by the blade and arranged to engage the wheel in the casing, for the purpose set forth.

2. In a rotary engine, the combination with a casing containing abutments, and wheels mounted in the casing at points adjacent to the abutments, of a rotary piston, blades carried by and movable with respect to the piston, and wheels carried by the blades and arranged to move past and engage the wheels in the casing to move the blades inward and enable same to pass the abutments.

3. In a rotary engine, the combination with a casing containing an abutment, and a wheel mounted -in the easing at a point adjacent to the abutment; of a rotary piston, a blade carried by and movable with respect to the piston, means for moving said blade outward, and a wheel carried by the blade and arranged to move past and engage the wheel in the casing to move the blade inward and enable same to pass the abutment.

4. In a rotary engine, the combination of a casing containing abutments, wheels mounted to freely rotate in the casing adjacent to the abutments, a piston arranged in the casing and having a notched hub, 21 web, and a peripheral portion in which there are radial sockets, bifurcated blades arranged in said sockets and having arms resting at oppo site sides of the web and in the notches of the hub, means for moving the blades outward, and wheels carried by the arms of the blades and arranged to engage the peripheries of the said wheels in the casing to move the blades inward and enable same to pass the abutments.

In a rotary engine, the combination of a casing containing an abutment, a wheel mounted in the casing adjacent to the abutment, a piston arranged in the casing and having a notched hub, a web, and a peripheral portion in which there is a radial socket, a bifurcated blade arranged in said socket and having arms resting at opposite sides of the web and in the notches oi the hub, means for moving the blade outward, and a Wheel carried by the arms of the blade and arranged to engage the wheel in the casing to move the blade inward and enable same to pass the abutment.

G. In a rotary engine, a piston comprising a notched hub, a web, and a peripheral portion having radial sockets and also having peripheral flanges provided with packing, bifurcated blades arranged in the sockets of the piston and having arms resting at opposite sides of the web and in the notches of the hub, means for moving said blades outward, and wheels carried by the arms of the blades;

in combination with a casing containing the piston and having abutments, and Wheels arranged in said casing and positioned to engage the wheels on the blades to move said blades inward to enable same to pass the abutments.

7. In a rotary engine, a rotary piston, blades carried thereby, and means for moving said blades outward, in combination with a casing containing the piston and having opposite abutments, steam ports at opposite sides of the same, steam chests communicating with said ports and each having an inlet port and an exhaust port for steam, hollow, reversing cylinders arranged to be turned in the steam chests and each having ports for registration with the first mentioned ports, a port for registration with the steam inlet port, and passages for effecting connection between the first mentioned ports and the exhaust ports, arms fixed to said rolling cylinders, a link connecting said arms, rocking cut-off valves arranged in and movable independent of the rolling cylinders and having ports for registration with the first mentioned ports of the rolling cylinders, and means intermediate the piston and the valves for operating the latter by the former.

In testimony whereof I, have hereunto set my hand in presence of two subscribing witnesses.

HENRY J. DUNCAN.

Witnesses JOSEPH HEUETT, STEVE MA'rIIIsoN. 

